Adjustable golf club with hydrodynamic lock-up

ABSTRACT

The various embodiments of the disclosure are directed to a golf club head having adjustable loft and lie angles, wherein the loft and lie angles are hydrodynamically locked during impact of the club head with the ball.

[0001] This application is a continuation-in-part of U.S. Pat. No. 6,348,009, issued Feb. 19, 2002, and entitled “Adjustable Golf Club With Hydrodynamic Lock-up”. All cited patents are incorporated by reference in their entirety for all purposes.

FIELD OF THE INVENTION

[0002] The present invention relates to golf clubs, and more particularly relates to a golf club head having adjustable loft and lie angles.

BACKGROUND OF THE INVENTION

[0003] In golf, clubs are used having varying loft angles to impart greater or lesser distance or height to the ball. Drivers having a slight angle from the vertical are used to drive the ball a great distance horizontally with a relatively flat trajectory. A putter with virtually no loft angle is used on the green itself. At intermediate distances, irons having varying loft angles measured from the vertical are used. Typically, larger loft angles are used for shorter distances. Most golfers use up to 14 clubs (limited by rule) with varying lofts at approximately four-degree increments, with each loft angle typically associated with a lie angle. The need for multiple clubs creates a number of disadvantages, such as the high cost of a complete or partial set, and the need for transportation of a bulky and heavy set of clubs, both to and on the course.

[0004] A number of adjustable golf clubs have been developed with the object of reducing the number of clubs required. Many designs have used one or more sets of teeth or splines to key-in the various desired loft angles. Adjustable club heads using splined shafts are exemplified by U.S. Pat. No. 1,219,417 to Vories; U.S. Pat. No. 2,305,270 to Nilson; U.S. Pat. No. 1,429,569 to Craig, U.S. Pat. No. 2,571,970 to Verderber, U.S. Pat. No. 3,601,399 to Agens et al; and U.S. Pat. No. 4,878,666 to Hosoda. Clubs employing multiple toothed rings for vernier adjustment are exemplified by U.S. Pat. No. 2,882,053 to Lorthiois; and U.S. Pat. Nos. 3,840,231 and 5,538,245 to Moore. A ratcheting vernier adjustment is taught in U.S. Pat. No. 5,133,553 to Divnick. Sealed containers having permeable elastomeric sheets sealed together and inflated with a gas having low permeability therethrough is taught in U.S. Pat. No. 4,287,250, to Rudy. A club head having variable loft and lie angles is taught in U.S. Pat. No. 2,962,286, to Brouwer. The teachings of the patents cited above are entirely incorporated herein by reference.

[0005] As the impact of the club head with the ball generates large forces and torques acting in unpredictable directions, various auxiliary fastening devices such as nuts, screws and levers have been used to lock-up the head so that the loft angle does not accidentally change during use. These auxiliary devices are undesirable, as they detract from the enjoyment of the game. They are also prone to failure with repeated use, due to over or under tightening, and to contamination or corrosion.

[0006] It would be desirable for a club to be self-locking, so that no auxiliary devices would be needed. It would also be desirable that the concentration of the golfer not be broken by the need to make complicated adjustments to the club. And it would be most desirable that the loft angle be changeable in one continuous and smooth motion by the golfer

SUMMARY OF THE INVENTION

[0007] The present invention provides a uniquely simple solution to the problems associated with adjustable golf clubs, and does so without requiring that the golfer remember arcane and complicated adjustment procedures. Rather, the instant invention provides a perfectly natural and aesthetically desirable look and feel for both the club and the adjustment thereof, while also enhancing the technical performance of the club.

[0008] An important feature of an adjustable club is that the loft and lie angles, once set, do not change during use. First of all, if the equipment is not reliable, the player's lack of confidence can negatively effect his game, and second, a club head that moves under impact conditions can damage the adjustment mechanism, and ruin the club. In the present invention, the head, once set at the desired loft and lie angles, is hydrodynamicly locked-up, and cannot move into an unlocked position due to the collision of the club with a ball. This lock-up is achieved automatically during impact conditions.

[0009] As golf is an aesthetic game, it is important that the head adjusts smoothly, substantially without noise or snap-back, and without requiring tools. It is also important that the adjustment is easily achieved without the need for calculation on the part of the golfer.

[0010] The present invention accomplishes the above and other objectives by dividing the working volume within the adjustable club head into at least three chambers: first and second chambers filled with an incompressible fluid, and a third chamber filled with a compressible fluid. The third chamber may be a discreet chamber, or may be the atmosphere.

[0011] The working volume within the club head comprises a splined (toothed) pivot shaft which mates with a splined inner cylinder surface fixed within the adjustable club head. It is desirable that both the exterior splined surface of the pivot shaft and the interior splined surface of the cylinder are segmented, with gaps therebetween, so as to reduce the total axial motion required to de-couple the splines while providing sufficient tooth area to resist rotation. When not being adjusted, the splines are aligned so as to prevent relative rotation, and the pressure of the gaseous fluid within the third chamber maintains this coupled axial alignment. The third chamber pressurizes the second liquid filled chamber by means of a flexible diaphragm or floating piston therebetween. The first chamber is pressurized by means of a fluid conduit between the first and second chambers, so that, at rest, the pressures in all three chambers are equal (and above atmospheric). Most typically, all chambers are coaxial with the pivot shaft, with the second chamber between the first and third chambers. The pivot shaft is non-parallel to the either the sole line, strike plane, or club head center line, so that the club head center line generates a cone of revolution about the pivot shaft when the club is rotated about the pivot shaft, thereby achieving varying lie and loft combinations as the club head is rotated. A description of the manner in which lie and loft angles are associated is taught in U.S. Pat. No. 2,962,286 to Brouwer, and entirely incorporated herein by reference.

[0012] The conduit between the first and second chambers restricts the rate of fluid flow between them. This results in a small pressure build-up within the first chamber relative to the second, resulting in a resistance and a smooth axial motion of the club head on the pivot shaft as the two are pressed together by the golfer during adjustment. During a stroke, while under impact conditions, the pressure build-up is much greater than it is during adjustment, and tends to resist axial motion and the resultant de-coupling of the splines. By way of example only, and not limitation, if one pound of force applied for one second is necessary to de-couple the splines during adjustment (this is the hydrodynamic force generated by fluid flow in the conduit only, and neglects the gas pressure in the third chamber, which must also be overcome), then, during an impact of the golf head with a ball lasting only one millisecond, a million pounds of force would be required to move the fluid through the conduit and thereby de-couple the splines. The force required is so much greater because the hydraulic force generated varies inversely with the square of the time period involved. If the impact period is three orders of magnitude smaller than the adjustment period, then the decoupling force required will be six orders of magnitude greater. This force resisting de-coupling is so large that the head remains effectively locked-up during the brief period of impact.

[0013] It is an object of the present invention to provide an adjustable golf club head so that lie and loft of the club can be varied by the user without tools.

[0014] It is another object of the present invention to provide an adjustable golf cub head having hydrodynamic lock-up during impact with a golf ball.

[0015] It is yet another object of at least one embodiment of the present invention to provide an adjustable golf club head having a plurality of strike faces.

BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The above as well as other objects of the invention will become more apparent from the following detailed description of the preferred embodiments of the invention, when taken together with the accompanying drawings in which:

[0017]FIG. 1 is a cross-sectional exploded view of a pivot cartridge showing the various elements of one embodiment of the invention.

[0018]FIG. 2A is a cross-sectional view of an assembled pivot cartridge according to an embodiment of the invention, with the cartridge in the distal or engaged position.

[0019]FIG. 2B is a cross-sectional view of an assembled pivot cartridge as in FIG. 2A, with the cartridge in the proximal or disengaged position.

[0020]FIG. 3 is a cross-sectional view of an assembled adjustable head comprising a pivot cartridge according to a preferred embodiment of the invention, with the head in the distal position.

[0021]FIG. 4A is a partial cross-sectional view of an assembled adjustable head according to an alternative embodiment of the invention, wherein a fluid cell is substituted for the piston of FIG. 3.

[0022]FIG. 4B is a partial cross-sectional view of an assembled adjustable head according to an alternative embodiment of the invention, wherein a diaphragm is substituted for the fluid cell of FIG. 4A.

[0023]FIG. 4C is a partial cross-sectional view of an assembled adjustable head according to an alternative embodiment of the invention, wherein a spring is substituted for or supplements the compressed fluid of FIG. 3.

[0024]FIG. 5 is a cross-sectional view of an assembled adjustable head according to an embodiment of the invention.

[0025]FIG. 6A is a partial cross-sectional view of an assembled adjustable head according to another embodiment of the invention, shown in the distal orientation, and wherein the hosel is integrated into the pivot shaft.

[0026]FIG. 6B is a partial cross-sectional view of the assembled adjustable head of FIG. 6A, shown in the proximal orientation.

[0027]FIG. 7 is a cross-sectional view of an assembled adjustable head according to another embodiment of the invention, with the head in the distal position, and with the pivot axis non-parallel to the sole line.

[0028]FIG. 8 is a right side view of the adjustable head shown in FIG. 7, with the pivot axis non-parallel to the strike face.

[0029]FIG. 9 is a cross-sectional view of an alternative embodiment of the pivot assembly.

[0030]FIG. 10A is an enlarged cross-sectional view of an embodiment of the plunger shown in FIG. 9.

[0031]FIG. 10B is an enlarged cross-sectional view of an alternative embodiment of the plunger shown in FIG. 10A.

[0032]FIG. 10C is an enlarged cross-sectional view of yet another alternative embodiment of the plunger shown in FIGS. 10A and 10B.

DESCRIPTION OF THE INVENTION

[0033] Herein, the following terms are given the following meaning: “Strike plane” is the plane that best approximates the strike face (e.g., removing any curvature thereof). “Sole line” is the line of intersection of the strike plane with the ideally flat playing surface (ground) when the club is oriented at the correct lie angle and in contact with the playing surface. “Lie” and “loft” are given the usual meanings.

[0034] An exploded view of a pivot cartridge for insertion into an adjustable club head according to a preferred embodiment of the instant invention is shown generally as numeral 3 in FIG. 1, and the assembled pivot cartridge is shown in the engaged (distal) position generally as numeral 1 in FIG. 2A and in the disengaged (proximal) position generally as numeral 1′ in FIG. 2B. Referring now to FIGS. 1, 2A, 2B, the pivot shaft 11, comprises a bearing surface 10 and a shaft extension 16. A plurality of exterior spline (toothed) segments 12 are spaced apart by exterior gap segments 14. A splined shaft 8 and threaded shaft extension 6 are provided for attachment with a hosel (not shown). The pivot shaft 11 mates with cylinder 30, comprising a bearing surface 22, having a diameter slightly larger than the diameter of the bearing surface 10 of the pivot shaft 11. Interior spline segments 24 engage exterior spline segments 12 when in the engaged position illustrated in FIG. 2A. A bushing 31 has a bushing ID 33 for press fitting or otherwise attaching to shaft extension 16, and a bushing OD 32, slightly smaller than the diameter of the bearing surface 28 of the cylinder 30, so that it may freely rotate and slide therein. A seal 18 fits into groove 20 of cylinder 30, and prevents fluid leakage from between the mating bearing surfaces 22, 10. Piston 60 having seal 64 fitting into groove 62 floats in bearing surface 28. Tapered hole 66 is plugged by tapered pin 68. Seal 17 fits in the groove 27 of the exterior surface of the cylinder 30.

[0035] In FIG. 2A, chamber 100 constitutes the first chamber, which is filled with a substantially incompressible fluid. This incompressible fluid may be any liquid or gel; but oil or grease are preferred, due to the lubricating action and prevention of corrosion of the internal components of the cartridge. In FIG. 2A, the pivot cartridge 1 is in the engaged (distal) position, while the pivot cartridge 1′, shown in FIG. 2B, is in the disengaged (proximal) position. (“Distal” and “proximal” refer to the relative position of the club head with inserted pivot cartridge, to the hosel.) In FIG. 2B, fluid has been driven from the chamber 100 of FIG. 2A through the engaged interior and exterior spline segments 24, 12, which together constitute a restricted conduit, to chamber 102. If the bushing OD 32 is larger or equal to the diameter of the bearing surface 10, chamber 102 constitutes the second chamber. If the bushing OD 32 is smaller than the diameter of the bearing surface 10, then fluid is also forced between the mating surfaces of the bushing OD 32 and the bearing surface 28 (a restricted conduit in series with the engaged interior and exterior spline segments) into chamber 106, which then constitutes the second chamber. In moving between the distal to the proximal positions, the fluid pressure in the first chamber increases by an amount that is generally proportional to the square of the rate of movement, and this increased pressure acts to resist the motion of the pivot shaft 11 relative to the cylinder 30. The primary purpose of chamber 106 is to provide volumetric compliance for the changing volume of the first chamber during motion. The first and second chambers and restricted conduit(s), i.e., the volume bounded by seals 18, 64, may be filled with an incompressible fluid by immersing the assembled cartridge 1 (sans piston 60) in the fluid and drawing and releasing a vacuum. The piston 60 may then be inserted so that air escapes through tapered hole 66, which is then sealed with tapered pin 68. Other means such as screws may be used to seal the hole 66, and the piston 60 may be also installed under vacuum so that no hole is necessary.

[0036] Turning now to FIG. 3, the club head, generally indicated by numeral 200, comprises the pivot cartridge 1, shown inserted in the engaged or distal position into the club support 13, which supports club strike face 7. The pivot cartridge 1 is shown mounted to hosel 4 by means of nut 2. Hosel 4 is the interface to handle shaft 5, by which the club is gripped and swung. Chamber 104, formed by the piston 60, the bearing surface 28 and the blind hole 108, is filled with a compressible fluid, preferably a gas or gas and liquid and/or gel mixture. This compressible fluid may be compressed and trapped during the installation of the pivot cartridge 1, as it is preferably press-fit into the blind hole 108. The compression of this fluid may be regulated by the position of the seal 17 along the cylinder 30, with excess fluid vented by means of groove 109 until the seal 17 makes contact with the open end of the blind hole 108, at which point further leakage is prevented. Knurled surface 23 is provided on the exterior of cylinder 30 to prevent rotation of the cylinder 30 within the blind hole 108. A heavy press fit, adhesives, pins, keys or brazing may also be used to prevent rotation. Insertion is facilitated by the prior assembly of the pivot cartridge 1.

[0037] Turning now to FIG. 4A, wherein the club head is generally indicated by numeral 201, an alternative configuration of the third chamber containing the compressible fluid is shown as fluid cell 35, which comprises a hollow flexible. Fluid cell 35 may comprise polymeric, elastomeric, rubber or other flexible materials resistant to the incompressible fluid and substantially impermeable to the compressible fluid. The fluid in the fluid cell 35 may be compressed during insertion of the pivot cartridge 1 in the same way as described above with reference to FIG. 3. While the compressible fluid may consist entirely of air, or of gases such as nitrogen, oxygen, argon, methane, ethane, propane, butane, fluoroform, neo-pentane, and others, there are advantages that accrue from using gases having intrinsically low diffusion rates due to large size and symmetrical molecular shape. Use of such gases would be especially valuable when used within a fluid cell comprised of rubber, elastomer, or polymer. Such gases would include perfluoropentane, perfluorohexane, perfluoroheptane, octafluorocyclobutane, perfluorocyclobutane, hexafluoropropylene, tetrafluoromethane, monochloropentafluoroethane, 1,2-dichlorotetrafluoroethane; 1,1,2-trichloro-1,2,2 trifluoroethane, chlorotrifluorethylene, bromotrifluoromethane, and monochlorotrifluoromethane, hexafluoroethane, sulfur hexafluoride, perfluoropropane, perfluorobutane and mixtures thereof. If the fluid cell is filled with one of this group, and with a less than atmospheric partial pressure of nitrogen and oxygen (and preferably no nitrogen or oxygen), then any air that might leak into the club head and mix with the incompressible fluid would, over time, tend come into contact with the surface of the fluid cell 35 and would diffuse into the fluid cell, as the fluid cell Composition may be altered to allow a slow rate of permeability for the atmospheric gases, while still preventing leakage of the inflatant gas. The fluid cell would thus act as a scavenger to rid the incompressible fluid of undesired compressible fluid, as the compressible fluid would undesirably tend to reduce the bias pressures generated during axial motion. For scavenging of air, the fluid cell inflatant gas should preferably have a permeability relative to the fluid cell of less than 0.1 times that of air, and preferably less than 0.01 times that of air.

[0038] In FIG. 4B, wherein the club head is generally indicated by numeral 202, the fluid cell is replaced with a diaphragm 37 held in place with clamp 39, forming the flexible side of chamber 104. In practice, the diaphragm 37 operates in the same manner as the fluid cell 35. Alternatively, the diaphragm 37 may be comprised of a thin gage metal, and the chamber would then be impermeable.

[0039] In FIG. 4C, wherein the club head is generally indicated by numeral 203, the pressure supplied by the compressible fluid in the third chamber is partially or completely replaced by a spring 34, operating on piston 60.

[0040] Turning now to FIG. 5, the pivot shaft 11 is attached to hosel 4 by means of a press fit with smooth shaft 9, which may also be welded to the hosel. The pivot shaft 11 is inserted into a through hole 110, into which external spine segments 24 are directly formed. A piston 74 serves with end cap 72 to trap a compressible fluid. Extrusion of the end cap 72 is prevented by snap ring 70. The club head is generally indicated by the number 205.

[0041] In FIG. 6A, an alternative construction is shown wherein the hosel 4 is integrated with the pivot shaft. The club head 204 is shown in the distal or engaged position. In FIG. 6B, the club head 204 is shown in the proximal or disengaged position. This proximal position also facilitates the reading the loft angle by way of the indicia 90.

[0042] Turing now to FIG. 7, yet another embodiment is shown wherein the chamber 111 acts as the first chamber, and is filled with an incompressible fluid. The motion of the plunger 76 into cup 78 as the club head 206 is moved from the distal to the proximal position drives fluid into the second chamber formed by the gap between piston 61 and cup 78. In this case, the third chamber constitutes the volume between seal 64 and seal 18, and is filled with a compressible fluid, which may comprise a gas, or gas and liquid and/or gel mixture. Hole 80 facilitates the insertion of the pivot cartridge by venting air during insertion. In FIG. 8, the right end view of a variation of the embodiment shown in FIG. 7 is illustrated, showing strike surface 40 (shown as a planar surface, and therefore coincident with the strike plane) having sole line 300. Strike surface 40 is oriented at angle B to pivot axis 15. As is true in all embodiments herein, the cub head may comprise a plurality of strike surfaces, such as second strike surface (and strike plane) 40′ comprising sole line 300′, which need not be oriented at the same angles (A and/or B) to pivot axis 15.

[0043] Turning now to FIGS. 9, three variations of the pivot assembly 350 are shown that may be used with any of the embodiments. First, hosel shaft 11 is continuous with and extends from bearing surface 10 by way of transition 19. Second, elastomeric spring 312 pressurizes incompressible fluid that occupies cavity 310, and all other cavities within club support 13, with the exception of cavity 314, which is in communication with the atmosphere via port 318. (Alternatively, cavity 314 may be filled with a flexible foam, thereby increasing the spring rate of spring 312 and keeping out water, port 318 may be covered with a porous material such as expanded polytetrafluoroethylene, or a sintered polymer or metal, or may be expanded in diameter so that spring 312 is substantially fully exposed.) Spring 312 is held in place by protective cap 316, and abuts plunger pin support 308, in which is mounted plunger pin 304. And third, plunger pin 304 partially fills blind cavity 302 in the distal end of pivot shaft 11. Motion of plunger pin 304 into cavity 302 generates a hydraulic pressure opposing this motion towards the proximal position.

[0044] Details of alternative embodiments of the plunger pin 304 are shown in relatively enlarged aspect in FIGS. 10A-C. While the pin may be solid, so that the force generated in moving the pin in either the proximal or distal direction is substantially the same, a check valve of any configuration may be incorporated in the plunger pin (or elsewhere in cavity 302). In FIG. 10A, conduit 306 extends from the distal end of plunger pin 304, and is in fluid communication with conduit 307. Elastic band 308 acts as a check, tending to restrict fluid from entering conduit 307 from the proximal end, but expanding to more freely allow fluid passage from the distal direction. The outside diameter of plunger pin 304 may be adjusted to allow the desired degree of backflow. Alternatively, grooves in the outside diameter may be provided, or an additional smaller conduit 335 may be provided that bypasses the check valve (not shown). In FIG. 10B, plunger pin 304′ comprises a check valve with ball 326 for blocking conduit 306, spring 324 for urging ball 326 into the blocked position, and retainer 329 comprising port 328. Backflow may be provided for by any suitable means, such as groove 335. In FIG. 10C, plunger pin 304″ comprises a check valve with slider block 333 having proximal conduit 330 in fluid communication with conduit 331. In the proximal position, slider block 333 would reside against retainer 329, allowing fluid passage through conduit 328 into conduit 330 and into conduit 306 via conduit 331. In the distal position, flow into conduit 306 would be blocked by contact with distal end 332. Back flow can be provided by channel 334, or by a gap between the outside diameter of slider block 333 and the inside diameter of cavity 302 (FIG. 9), or by a groove in the outer surface of slider block 333, or by any other means.

[0045] Although only a few exemplary embodiments of this invention have been described in detail above, those skilled in the art will readily appreciate that many modifications are possible in the exemplary embodiments without materially departing from the novel teachings and advantages of this invention. Accordingly, all such modifications are intended to be included within the scope of this invention as defined in the following claims. In the claims, means-plus-function clauses are intended to cover the structures described herein as performing the recited function and not only structural equivalents, but also equivalent structures. 

I claim:
 1. A golf club head comprising an adjustable loft angle and an adjustable lie angle, comprising: a strike plane; a sole line; a pivot shaft comprising an axis mounted in the golf club head, wherein said axis is not parallel to said sole line and/or said strike plane; means for preventing rotation of the golf club head about said pivot shaft; means for axially biasing said golf club head on said pivot shaft into a rotatably locked position relative to said pivot shaft; and means for generating a hydrodynamic bias pressure, said bias pressure resisting axial movement of said club head relative to said pivot shaft during impact of the golf club head with a golf ball; whereby the loft and lie angles of the club head remain unchanged during impact with said golf ball, and whereby the loft and lie angles may be changed simultaneously by rotating said surface about said pivot shaft.
 2. A golf club head comprising an adjustable loft angle and an adjustable lie angle, as recited in claim 1, wherein said means for generating a hydrodynamic bias pressure comprises a first chamber comprising a first variable volume, a second chamber comprising a second variable volume, and a restrictive fluid conduit placing said first chamber in fluid communication with said second chamber; and wherein said first chamber, said second chamber and said restrictive fluid conduit are filled with a substantially incompressible fluid, whereby axial motion of the club head on said pivot shaft flows said incompressible fluid between said first chamber and said second chamber.
 3. A golf club head comprising an adjustable loft angle and an adjustable lie angle, as recited in claim 2, wherein said axial motion of the golf club head on said pivot shaft creates a pressure differential between said first chamber and said second chamber, wherein said pressure differential tends to resist said axial motion, and said pressure differential tends to increase as the velocity of said axial motion increases.
 4. A golf club head comprising an adjustable loft angle and an adjustable lie angle, as recited in claim 2, wherein said means for axially biasing said golf club head on said pivot shaft comprises a spring.
 5. A golf club head comprising an adjustable loft angle and an adjustable lie angle, as recited in claim 2, wherein said means for axially biasing said golf club head on said pivot shaft comprises a third chamber comprising a variable volume, wherein said variable volume comprises a compressible fluid under a pressure greater than atmospheric pressure, wherein said compressible fluid urges the club head into a non-rotatable position on said pivot shaft, and wherein said compressible fluid pressurizes said incompressible fluid.
 6. A golf club head comprising an adjustable loft angle and an adjustable lie angle, as recited in claim 5, wherein said compressible fluid comprises a gas.
 7. A golf club head comprising an adjustable loft angle and an adjustable lie angle, as recited in claim 5, wherein said means for preventing rotation of the golf club head about said pivot shaft comprises axially aligned splines.
 8. A golf club head comprising an adjustable loft angle and an adjustable lie angle, as recited in claim 5, wherein said third chamber comprises a piston slideably mounted within the golf club head.
 9. A golf club head comprising an adjustable loft angle and an adjustable lie angle, as recited in claim 5, wherein said third chamber is isolated from said second chamber by a flexible diaphragm.
 10. A golf club head comprising an adjustable loft angle and an adjustable lie angle, as recited in claim 5, wherein said third chamber comprises a metal bellows.
 11. A golf club head comprising an adjustable loft angle and an adjustable lie angle, as recited in claim 5, wherein said third chamber comprises a flexible fluid cell comprising a continuous surface.
 12. A golf club head comprising an adjustable loft angle and an adjustable lie angle, as recited in claim 5, wherein said flexible fluid cell comprises a gas comprising a permeability through said fluid cell surface that is less than that of either nitrogen or oxygen.
 13. A golf club head comprising an adjustable loft angle and an adjustable lie angle, as recited in claim 11, wherein said fluid cell comprises a sealed volume; wherein said continuous surface comprises a permeable elastomeric, polymeric, or rubber material surrounded by said incompressible fluid; and wherein said sealed volume is inflated with a compressible fluid to a pressure greater than atmospheric.
 14. A golf club head comprising an adjustable loft angle and an adjustable lie angle, as recited in claim 13, wherein said compressible fluid comprises an inert, non-polar gas.
 15. A golf club head comprising an adjustable loft angle and an adjustable lie angle, comprising: a first strike plane; a first sole line corresponding to said first strike plane; a pivot shaft comprising an axis mounted in the golf club head, wherein said axis is not parallel to said first strike plane and/or said first sole line; a first closed variable volume substantially filled with an incompressible fluid; a second closed variable volume substantially filled with an incompressible fluid; and at least one restrictive conduit for fluid communication between said first closed variable volume and said second closed variable volume whereby fluid in said first closed variable volume may be flowed by the externally applied compressive force into said second closed variable volume, while said restrictive conduit preventing substantial fluid flow while striking said golf ball; and wherein the golf club head comprises a first and a second axial end orientations on said pivot shaft; wherein said first orientation is distally oriented relative to said second orientation; wherein said first orientation is non-rotatable relative to said pivot shaft; and wherein said second orientation is rotatable relative to said pivot shaft.
 16. A golf club head comprising an adjustable loft angle and an adjustable lie angle, as recited in claim 15, wherein said incompressible fluid comprises a lubricating oil or grease.
 17. A golf club head comprising an adjustable loft angle and an adjustable lie angle, as recited in claim 15, further comprising a second strike plane.
 18. A club head comprising adjustable loft and lie angles, comprising: a first surface for impacting a golf ball; first sole line corresponding to said first surface; at least a second surface for impacting said golf ball; a second sole line corresponding to said second surface; a pivot shaft comprising an axis mounted in the golf club head, wherein said axis is not parallel to said first sole line and/or said second sole line; means for preventing rotation of the club head about said pivot shaft; means for axially biasing said club head on said pivot shaft into a rotatably locked position relative to said pivot shaft; and means for generating a hydrodynamic bias pressure, said bias pressure resisting axial movement of said club head relative to said pivot shaft during impact of the club head with said golf ball; whereby the loft and lie angles of the club head remain unchanged during impact with said golf ball, and whereby the loft and lie angles may be changed simultaneously by rotating said surface about said pivot shaft.
 19. A golf club head comprising adjustable loft and lie angles, as recited in claim 18, wherein said means for generating a hydrodynamic bias pressure comprises a first chamber comprising a first variable volume, a second chamber comprising a second variable volume, and a restrictive fluid conduit placing said first chamber in fluid communication with said second chamber; and wherein said first chamber, said second chamber and said restrictive fluid conduit are filled with a substantially incompressible fluid, whereby axial motion of the golf club head on said pivot shaft flows said incompressible fluid between said first chamber and said second chamber.
 20. A golf club head comprising adjustable loft and lie angles, as recited in claim 19, wherein said axial motion of the golf club head on said pivot shaft creates a pressure differential between said first chamber and said second chamber, said pressure differential tending to resist said axial motion, and said pressure differential tending to increase as the velocity of said axial motion increases. 